With the advent of the Internet, society has witnessed the expansion of a global packet-switched network into an ever-increasing number of homes and businesses. This has enabled an ever-increasing number of users to communicate with each other, primarily utilizing electronic communications, such as e-mail and instant messaging. Meanwhile, advances have been made in delivering voice communication over packet-switched networks, driven primarily by the cost advantage of placing long-distance calls over the packet-switched networks, but also by the ability to deliver advanced service features to users. This cost advantage can be enjoyed by both a service provider delivering the voice communication over the packet-switched network service (in a form of lower operating cost), as well as the user who subscribes to the services of such a service provider (in a form of lower service subscription fees). Technology dealing with the delivery of real-time voice communication over the packet-switched network is generally referred to as media-over-packet, voice-over-IP or, simply, VoIP.
As is well appreciated in the art, the delivery technology for VoIP is fundamentally different from the delivery technology for the traditional PSTN-based systems. Thus, certain features that are available to customers in the PSTN-based environment are not necessarily native to the VoIP environment. At the same time, customers may have become accustomed to having these features and may expect to have these features available to them in the VoIP environment, if they are to adopt VoIP-based communication as the primary means for establishing voice connections.
One example of a feature that is available in PSTN-based systems, but is not native to VoIP-based systems, pertains to the user experience when attempting to establish a communication session. Specifically, consider the scenario where a particular user has a single PSTN telephony line coming into the user's household with several telephones connected to the single telephony line. If a first member of the household is engaged in a voice conversation using one telephone and if a second member of the household picks up another telephone, the second member of the household will automatically join the voice conversation maintained by the first member of the household. However, this effect does not occur in VoIP-based systems, in which calls are established on a point-to-point basis. As a result, a VoIP version of this familiar feature is not presently available and, thus, VoIP providers may be less likely to attract customers away from the PSTN paradigm.
Therefore, it would be beneficial for VoIP service providers to be able to mimic this user experience in the VoIP environment.